predicates(3)

NAME

im_region_create, im_region_free - region creation and destruction

#include <vips/vips.h>
REGION *im_region_create( im )
IMAGE *im;
int im_region_free( reg )
REGION *reg;

These functions create and destroy regions on images. Regions are used for PIO, see accompanying documentation. Regions have type: typedef struct {
Rect valid /* Area of im represented */
IMAGE *im; /* im we are defined on */

... more fields, all private and used for
... housekeeping; } REGION;
im_region_create(3) returns a pointer to a new region, or NULL on error. Regions are made blank, with no input or output possible. See im_prepare(3), im_generate(3), im_start_one(3) and IM_REGION_ADDR(3).
im_region_free(3) frees a region and any resources associated with that region. When an image is closed, all regions which have been created on that image are automatically freed.

All int-valued functions return zero on success and non-zero on error.

National Gallery, 1993